DLP Technology for Smart Screenless TVs

Hello, viewers, and welcome to this TI.com training. I am Philippe Dollo of the DLP Pico Projection Team, and today we're going to be discussing how to leverage the expansive DLP products portfolio to design for a popular and growing flavor of projector products-- screenless TV.
Screen less TV products come in a wide variety of shapes and sizes. This is driven by the variety of applications within the screenless TV space. For instance, a mobile smart TV projector will provide the picture quality you expect from DLP while maintaining a small enough form factor for portability and guaranteeing sufficient power performance for everyday needs. Meanwhile, a DLP laser TV projector will put emphasis on high brightness and performance to deliver a premium cinema experience.
Today, we will first go over the components that make up a DLP screenless TV. Understanding the DLP chipset will make it much easier to incorporate it into a full system. Next, we will address two of the major screenless TV applications. These are mobile smart TV and laser TV. We will discuss how to design for each of these applications, and how you can leverage DLP technology to do so. Finally, we will provide links to valuable resources that make integration and use of DLP technology into your screenless TV project as seamless as possible.
DLP provides a number of key advantages for screenless display applications. When designing with DLP, one should focus on bringing out these advantages to help differentiate their product. DLP technology offers unparalleled optical efficiency, contrast, and speed. These traits extend to the gamut of possible display resolutions without sacrificing image quality. To further enhance picture quality for display projection applications, advanced image processing algorithms act on incoming video data to optimize the viewing experience for each individual chipset. The screenless TV market is a growing one, so it is important to select the best DLP chipset for your target application and make your product stand out.
However, it is important to realize that a screenless TV is not just the DLP chipset you choose to employ in it. In order to deliver a premium experience, the DLP chipset must be integrated into a full system with smart connectivity and multimedia capabilities. The DLP projection, which is capable of filling any surface with a big screen display, needs a robust audio system to deliver a cinema experience.
Meanwhile, users today demand video accessibility anywhere, which is possible now thanks to the wide array of cloud services accessible via Wi-Fi and LTE. To tie it all together, a strong embedded operating system, such as Android, is needed to both stream media, as well as control the DLP and sound systems.
Let's examine what the DLP chipset may look like within the scope of a complete system. A host processor will typically drive the rest of the components through its embedded operating system. As such, it will stream video and audio individually to the DLP controller and a DSP network, respectively.
The DLP controller will, in most cases, interface with the outside world via a combination of I2C, for system commands, and either parallel or DSI interfaces for video data. A parallel interface provides the benefit of being simpler to implement with a full 24-bit RGB bus, while DSI consolidates this into as few as six lines for differential power, clock, and data.
Within the DLP portion of the system, there are numerous components to break down. In this example, we will use one of our 720p chipsets featuring the DLP3010 DMD. The DLPC3438, which serves as the controller for the chipset, receives video data from the host processor. It then uses this data to drive the DLP3010 digital micromirror device, or DMD, with an image. Meanwhile, the DLPA3000 functions as a power management IC for both the DLP3010 and the DLPC3438.
On top of providing power to the rest of the DLP chipset, it also drives the RGB LEDs, which, in tandem with instructions from the DLPC3438, help produce an image on the DLP3010 DMD. This is just one of many similar chipsets in the DLP Pico portfolio, which is well suited for mobile smart TV and other power sensitive applications. Later in this training, we will touch on other chipsets more well-suited to laser TV cinema applications.
The DMD is part of the optical path for the light image. As such, it lives in a systems optical engine, which also has its optics used to produce an image output with the desired brightness, size, and throw ratio. Good design of this optical engine is crucial to achieving the highest performance possible from the DLP chipset. The LEDs, optics, and DMD size must all be balanced to provide the highest brightness, while minimizing size, power consumption, and heat production.
To assist with the design of this critical component, a number of optical design manufacturers, or ODMs, provide rapid prototyping platforms that use our chipsets. By leveraging these ODMs, it is possible to accelerate development, production, and revenue without compromising on image quality.
For more advanced projects that use atypical optical engines or design constraints, we recommend looking at the TI design network to discover potential design partners and seek further assistance.
Now that we have explored the DLP chipset and its place in a screen TV system architecture, we will next examine how the system design may differ depending on your target application. The two categories of applications we will discuss here are mobile smart TV and laser TV.
Mobile smart TV applications encompass a range of products which provide smart functionality, such as streaming and an embedded operating system, into a portable package. Since the entire multimedia platform is self-contained, this portability allows users to cast their content to virtually any surface at any time. This allows users to bring television out of the living room anywhere they like.
As a result of this, mobile smart TV products have a particular need for efficiency and scalability. This is possible using DLP products from the DLP Pico portfolio. Thanks to the pixel architecture provided by DLP, high contrast ratio and great image quality are attainable in a small package. Since the DMDs are illuminated by freely controllable LEDs, the duty cycles of each color can be freely configured to achieve a wide gamut of color temperatures.
DLP Pico chipsets are also designed with power efficiency in mind, to enable sustained use on battery power. Some of the mobile smart TV examples on the market today show the caliber of products you can expect from this application category.
The DLP Pico portfolio has grown to fulfill a wide range of product scales. The 0.2 inch chipsets, such as our WVGA offering, provide the smallest possible size for maximum portability, while maintaining a 40 inch screen size in well-lit rooms. As the screen size increases to 55 inches, larger chipsets, such as the 0.47 inch 1080p and the 0.47 inch 4K chipsets satisfy designs willing to sacrifice a measure of portability for higher image quality.
All of the chipsets seen here use RGB LEDs as a light source to enable strong power efficiency. Picking the right DMD size is critical, as it influences the total brightness which can be projected from the system and simultaneously influences the power consumption and size of the system. Fortunately, the DLP Pico product portfolio provides enough granularity to capture the needs of any mobile smart TV project.
Although image quality and power consumption are crucial in a mobile smart TV design, it is important not to forget the optics, multimedia operating system, and physical design of your system. Making use of advanced video protocols, such as DSI, can allow you to design a robust DLP system, while saving room for connectivity options. Wi-Fi, Bluetooth audio, and USB Type C can go a long way to providing a premium user experience.
When designing a power conscious system such as that of a mobile smart TV, one should pay close attention to where the power budget goes in their system. The optical engine, which contains the RGB LEDs driving your DMD, consumes most of the system power during operation. So how you configure your system brightness will impact running time greatly.
However, standby power is just as important. Writing software that saves power whenever possible will ensure there isn't any waste on a single charge. Wi-Fi, for example, is infamous for draining system power to unwary users on many mobile devices. For a more dedicated look at mobile smart TV design considerations, I recommend reviewing our mobile smart TV training course on TI.com.
As with mobile smart TV, laser TV applications also benefit greatly from the contrast and image quality provided by DLP technology. However, instead of using LEDs as an illumination source, laser TVs use laser phosphor light sources for illumination. If you couple these light sources with the larger DMDs provided in the DLP cinema chipsets, your system is capable of producing huge screen sizes and projector brightness, making them impressive living room set pieces.
Like with our DLP Pico chipset portfolio, a range of different DLP cinema chipsets are available to implement based on your brightness and resolution needs. The larger pixel pitch and resolutions in these chipsets will help make the most use of the high brightness provided in a laser phosphor set up. Of course, with this new setup comes new design considerations.
A laser phosphor illumination source, which typically uses a color wheel, can have a varying number of lasers or color wheels in it. A basic design with a single laser and color wheel, made up of four segments, is shown here. In a typical LED system, each color is programmed to have a particular duty cycle out of a full frame in order to achieve a particular white point. In a laser based system, however, the laser is shining directly on the color wheel, which rotates to produce each of the segments or colors in the system.
As such, this duty cycle is inherently fixed by the segment sizes of the color wheel. This is different from an LED system, because in an LED system, the three LEDs can be programmed to have their duty cycles controlled independently of one another. Because of this, greater care must be taken to consider the desired color balance and its impact on the system design. A different laser brightness or color balance could result in greater power consumption or heat production.
In addition to color balance and brightness, design of the optical module must satisfy screen size requirements. Unlike with mobile smart TV applications, laser TV systems are expected to be relatively immobile. As such, it's up to the designer to think about where they expect the user to be placing their system during normal operation.
In screen size calculations, the ratio of the image projection distance to its width is the throw ratio. By having a short throw system, the laser TV unit can be placed closer to the screen or wall and present a stunning DLP image without being in an intrusive position.
While there are additional design considerations necessary when designing a laser TV optical module, the results can be incredible. For more information on some of these design considerations, check on our laser TV white paper on TI.com.
The DLP Pico and DLP cinema chipset portfolios are expansive, so let's review some of the resources we offer for you to take advantage of when developing your screenless TV system. For DLP Pico products, many off-the-shelf, optical modules, and even EMS are available on TI.com for purchase. With six EDMs available, most chipsets are easy to evaluate out of the box. These EDMs are each accompanied by a matching TI design which features all of the schematics, layout files, and bill of materials documents you may need to spin the design into a product of your own. For DLP cinema, a similar breadth of support collateral is available. In both cases, we recommend accessing the E2E community forum to get help with technical questions you may have after you've started your design.
If you're interested in designing a screenless TV system from the ground up using DLP technology, we recommend following the design flow shown. After taking some time to review training materials on TI.com, you should find an evaluation module that matches your target chipset. Then, you can leverage the accompanying TI design as a template to develop your own system, adding multimedia components and a host processor as necessary. For assistance with optical design, you can seek assistance from optical design manufacturers employing DLP technology in their products.
Thank you for listening to this online training, and we hope you have a pleasant experience using our DLP products in your screenless TV design.

Description

May 7, 2018

This system-level training covers the advantages and design consideration that make DLP technology a leader in the fast growing market of screenless TVs. End equipment appllications such as mobile smart TV and laser TV offer customers unique product differentiation, and feature several key TI subsystems. An overview of how to design for these applications, the DLP products ecosystem, and key customer concerns will be addressed.